Igniter



June 30, 1964 B. A. LINDBERG IGNITER Filed July 1, 1960 INVENTOR. BIRGERA. LINDBERG ATTORNEY 3,139,558 IGNITER 3,139,558 Patented June 30, 1964coil supporting brackets 24 and25 and two L-shaped terminal members 26and 27 are electrically connected Birger A. Lindberg, Inglewood, Calif.,assignor to Minne-' This invention relates to igniters'for gas burnersand,

more particularly, to a hot wire type ofigniter for igniting a pilotburner for a main gas burner.

This type of igniter is generally well known in the prior art but theprior art igniters have the common fault of being short lived. Due tothis fault, burner installations making use thereof have requiredfrequent service calls to replace burned out igniters. I

It is one of the objects of this invention to provide hot wire type ofigniter which will function as well as the prior art igniters yet have amuchlonger life.

Another object of the invention is to provide a hot wire type of igniterwherein the ignition coil is of much shorter length than prior artigniters. I i

A still further object of the invention is to provide an igniter for apilot burner wherein resistance means is placed in series with theigniter coil so as to reduce the length of the igniter coil, theresistance being concealed within the support for the igniter coil.

A further object of the invention is to provide an igniter wherein theignition coil, resistance means in series therewith and thelead wirestherefrom are so balanced or proportioned that the ignition coil willoperate properly with fluctuations in'the voltage ofthe source ofelectrical i FIGURE 1 is a side elevational view of a thermo electricgenerator embodying'theinvention, with portions thereof broken away; and

together by means of resistors 28 and 29. The resistor 28 has aresistance of .042 to .055 of an ohm and is spot Welded to the short legof the bracket 24 and to the intermediate portion of the long leg of theterminal member 26. The resistance29 is substantially the same as thatof 28 and is similarly connected to the bracket 25 and the terminal 27.The shape of the terminals, resistors, and brackets are such that theywill fit in the grooves in the blocks, half of the width or thickness ofthe members being in one block and the other half in the other block.The outer ends of the bracket members 24 and 25 are notched at 30 and31, respectively, to receive one end each of an igniter coil 32. Theends of the coil are held in the notch by staking or squeezing thebracket member against the wire and/ or welding or silver soldering theends to the bracket members. I The igniter wire, sometim'esca'lled theglow coil, is an alloy of 80% platinum and 20% rhodium and is preferably.015 of an inch in diameter. It has a resistance of .035 of an ohm to.040 of an ohm. This resistance "range for the glow coil as well as forthe resistorin series therewith is based on the use of the igniter in alow voltage igniter circuit having a power source of 2.5 volts. Ifhigher or lower power supplies are used, the resistance ranges mustcorrespondingly be changed.

The gas deflector plate 14 has a curved and beveled projection 14a thatextends laterally and downwardly into and slightly through a notch 15ain the upper surface of the burner 15 to deflect gas. issuing from theburner up over and around the glow coil 32 where it may be ignited tocause ignition of the other gas issuing from the burner 15.

FIGURE 2 is an elevational view of the igniter with one section of thehousing for theigniterremoved.

The igniteris illustrated as being mounted on a sup porting bracket 11by means of a rivet 12 extending through two molded porcelain blocks 13,through the upper portion of an arm of the bracket 11 and through a gasdeflector plate 14 on the other side of the porcelain blocks from thebracket 11.

In FIGURE 2 of the drawing, the terminal 21 is schematically shown asbeing connected through a lead fifthor one-sixth of the total resistanceof the igniter circuit to the two ends of the secondary of thetransformer. By thus balancing the resistances of the igniter or glowcoil, the resistance means in the housing of the igniter The bracket 11has two spaced and apertured arms.

11a whichstraddle the base of a burner 15 so that the bracket can beclamped to the base of a pilot burner by tightening a bolt 16 extendingthrough the two arms 11a. The burner is mounted in any suitable mannerin a second bracket 17 which also supportsa thermocouple 13 in spacedrelation to the burner 15 for heating thereby. The bracket 17 is adaptedto be bolted or otherwise secured to a main burner.

As can be best seen in FIGURE v2 of the drawing, the two inner surfacesof the blocks 13 have L-shaped grooves 19 and 20 formed therein whichextend from the and the resistance of the lead wires, variations in thesupply voltage of volts to 132 volts will not cause burning out of theigniter coil and a reduced voltage from 120 volts to 102 will givesatisfactory performance.

Due to the shortness of the coil 32, its light weight and the span,between its supporting brackets, there is no chance of shortening thelength of the life of the coil."

This is due to the fact that there is nochance that the Weight of thecoil will cause sagging thereof so as to cause the upper portions oftheloops to come together and reduce the resistance of the coil and,thereby, cause burning out of the coil. I

While I-have described the preferred embodiment of the invention above,it is to be understood that the scope of the invention is to bedetermined from the appended claims, it being obvious thatmodificationsmay be made in the invention without departing from thespirit thereof.

grooves 22 and 23 extend in spaced relationship with each other and thegrooves 19 and 20 from the base of the groove 21 to a point near thelower end of the blocks,

at which point, they converge and join with grooves 19 I claim as myinvention:

1. In a low voltage igniterfor a gas burner, the combination comprisinglead Wires of approximately 3 of the igniters total resistance, anigniter coil of approximately of the igniters total resistance andresistance means of approximately of the igniters total resistance inseries with said leads and coil, the eflective length of the wire ofsaid coil being less than one inch and the effective length of the coilbeing less than /2 inch.

2. In a low voltage igniter system for a gas burner, the combinationcomprising lead Wires of from .025 to .040 of an ohm, an igniter coiloffrom .035 to .040 ohm, resistance means of from .085 to 0.1 of an ohmin series with said leads and coil, the effective length of the wire ofsaid coil being less than one inch and the effective length of the coilbeing less than /2 inch, and means for supporting said lead wires andignition coil and resistance. means on a pilot burner and for deflectinggas from the burner to said igniter coil.

3. A gas igniter, for use in a 2.5 volt ignition system,

comprising a pair of abutting insulation blocks, grooves extending in atortuous path in at least one of the abutting surfaces of said blocks, apair of conductor brackets of negligible resistance extending into andbeyond one end of said grooves, a glow coil of platinum-rhodium wirehaving an effective length of less than one inch and extending betweenand secured to the projecting ends of said brackets, said coil having aresistance between 0.035 ohm and 0.040 ohm, a pair of terminalsextending into and beyond the other end of said grooves of said blocks,and resistance means of between 0.085 ohm and 0.11 ohm electricallyconnecting said coil and terminals, the total resistance between theterminals being between 0.135 and 0.145 ohm. i 4. A gas igniter, for usein a low voltage ignition system, comprising an insulation block, a pairof conductor brackets of negligible resistance extending into andprojecting out of said block, a glow coil extending between and securedto the projecting ends of said brackets, said coil having a resistancebetween 0.035 ohm and 0.040 ohm, a pair of negligible resistance leadsextending into and projecting from said block, and resistance means ofbetween 0.085 ohm and 0.11 ohm positioned within said block andelectrically connecting said coil and leads.

5. The combination defined in claim 4, wherein the effective length ofthe wire of said coil is less than one inch.

6. The combination of claim 5, wherein the effective length of said coilis less than /2 inch.

7. A gas igniter, for use in a 2.5 volt ignition system, comprising a.pair of abutting insulation blocks, a pair of complementary groovesextending in a tortuous path in the abutting surfaces of said blocksfrom one end thereof to the other, a pair of conductor brackets ofnegligible resistance extending into and beyond one end of said grooves,a glow coil of platinum-rhodium material extending between and securedto the projecting ends of said brackets, said coil having a resistancebetween 0.035 ohm and 0.040 ohm, resistance means of between 0.085 ohmand 0.11 ohm in said grooves and electrically connected to said coil,the total resistance across said glow coil and said resistance meansbeing between 0.135 ohm and 0.145 ohm, and a pair of lead wireselectrically connected to said resistance means and glow coil and havinga combined resistance between /5 and /5 of the total resistance of thecombination.

8. A gas igniter as defined in claim 7 in combination with means forsupporting said igniter adjacent a burner and means for deflecting aportion of a gas issuing from said burner to said igniter coil. 9. Thecombination defined in claim 8 wherein said means for supporting saidigniter adjacent a burner and said means for deflecting gas are securedto said igniter on opposite sides thereof by means of a single fasteningmeans extending through both of said means and said igniter.

References Cited in the file of this patent UNITED STATES PATENTS1,026,848 Brown May 21, 1912 1,118,942 Lyon Dec. 1, 1914 1,639,258 CohenAug. 16, 1927 2,360,607 Kautiman et a1 Oct. 17, 1944 2,384,797 Cerny etal Sept, 18, 1945 2,487,753 Cohn Nov. 8, 1949 2,487,754 Cohn Nov. 8,1949 2,492,755 McCollurn Dec. 27, 1949 2,530,827 Lakota et al Nov. 21,1950 2,625,990 Smith Jan. 20, 1953 2,744,569 Hoff May 8, 1956 2,751,973Meusy June 26, 1956 2,761,947 Rice et'al. Sept. 4, 1956 2,850,084Kunzler Sept. 2,- 1958 2,912,623 Tuttle Nov. 10, 1959

1. IN A LOW VOLTAGE IGNITER FOR A GAS BURNER, THE COMBINATION COMPRISINGLEAD WIRES OF APPROXIMATELY 2/12 OF THE IGNITER''S TOTAL RESISTANCE, ANIGNITER COIL OF APPROXIMATELY 3/12 OF THE IGNITER''S TOTAL RESISTANCEAND RESISTANCE MEANS OF APPROXIMATELY 7/12 OF THE IGNITER''S TOTALRESISTANCE IN SERIES WITHSAID LEADS AND COIL, THE EFFECTIVE LENGTH OFTHE WIRE OF SAID COIL BEING LESS THAN ONE INCH AND THE EFFECTIVE LENGTHOF THE COIL BEING LESS THAN 1/2 INCH.